websocket: fix transfer conn concurrent op #1033

	name: Build-Linux

	on:
	push:
	branches:
	- master
	- dev
	pull_request:
	branches:
	- master
	- dev

	env:
	GO111MODULE: off

	jobs:
	Build-Linux:
	name: Build-Linux
	strategy:
	fail-fast: false
	matrix:
	go: [1.18.x]
	os: [ubuntu-latest]
	runs-on: ${{ matrix.os}}
	steps:
	- name: install golang
	uses: actions/setup-go@v2
	with:
	go-version: ${{ matrix.go }}
	- name: checkout
	uses: actions/checkout@v2
	- name: go env
	run: \|
	printf "$(go version)\n"
	printf "\n\ngo environment:\n\n"
	go get -u github.com/lesismal/nbio/...
	ulimit -n 30000
	go env
	echo "::set-output name=short_sha::$(git rev-parse --short HEAD)"
	- name: go test
	run: go test -covermode=atomic -timeout 60s -coverprofile="./coverage"

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